Learn Hardcore Spanish (Latin America): Revisamos los errores uno por uno.

to review / go over (look through something carefully)
- Revisamos los errores uno por uno. = We review/go over the mistakes one by one.
to check / inspect
- Revisamos el documento. = We check the document.

It does not automatically mean to correct. That would usually be corregir:

Corregimos los errores. = We correct the mistakes.

So in your sentence, revisamos focuses on looking at the mistakes carefully, not necessarily fixing them, unless context clearly implies that.

Why isn’t nosotros used? Why not Nosotros revisamos los errores uno por uno?

In Spanish, subject pronouns (yo, tú, él, nosotros, etc.) are often dropped because the verb ending already shows who is doing the action.

Revisamos can only be “we” (first person plural), so nosotros is implied:
- Revisamos los errores uno por uno. = We review the mistakes one by one.

You add nosotros only when you want to emphasize or contrast:

Nosotros revisamos los errores, no ellos.
We review the mistakes, not them.

In neutral, everyday speech, leaving out “nosotros” is more natural.

Is revisamos present tense or past tense here?

For -ar verbs like revisar, the form revisamos is the same in:

Present tense (we review / we are reviewing)
Preterite tense (we reviewed / we checked)

So revisamos can mean either:

Present: We review / we check
Past (preterite): We reviewed / we checked

You know which one it is only from context or time markers:

Cada semana revisamos los errores uno por uno.
Every week we review the mistakes one by one. (present)
Ayer revisamos los errores uno por uno.
Yesterday we reviewed the mistakes one by one. (past)

Your isolated sentence could be either present or past; context decides.

Why do we say los errores and not just errores?

Spanish uses definite articles (el, la, los, las) more often than English, especially when talking about specific, known things.

Revisamos los errores uno por uno.
→ The speaker has specific errors in mind, probably the ones in a text or exercise they’re working on.
→ Literally: We review *the errors one by one.*

If you say revisamos errores, without los, it sounds more general and abstract, like a description of what you do in your job:

En mi trabajo revisamos errores de programación.
At my job we review programming errors. (errors in general)

Here, the definite article “los” tells you:
→ these particular errors (the ones we’re working on now).

Could I say revisamos errores uno por uno? Is that wrong?

It’s not grammatically wrong, but it sounds less natural in most contexts because Spanish tends to specify which errors:

Revisamos errores uno por uno.
→ Sounds like describing a procedure in a very general way: “We review errors one by one” (in general).

Most of the time when you say this sentence, you mean the errors in this document, on this test, etc., so you’d say:

Revisamos los errores uno por uno. ✅ (most natural in context)

Why is it errores (masculine) and not feminine? How do I know the gender?

Error in Spanish is a masculine noun:

el error → the error
los errores → the errors

There isn’t a rule that says all words ending in -r are masculine, but many are:
el color, el amor, el profesor, el dolor, etc.

You just need to learn the gender with the noun:

el error (masc.)
la falta (fem.) → the mistake / the fault

So:

el error grave (masc.)
la falta grave (fem.)

The article and any adjectives must match the gender and number of the noun.

What does uno por uno literally mean? Is it the same as “one by one”?

Yes. Uno por uno is a set expression that means exactly “one by one” or “one at a time.”

uno = one
por = by / per

So:

Revisamos los errores uno por uno.
We review the mistakes one by one.

You’ll also hear uno a uno, which is very similar:

Revisamos los errores uno a uno.
Also means We review the mistakes one by one.

In everyday language, uno por uno and uno a uno are generally interchangeable here. Some speakers might feel uno a uno sounds a bit more formal or written, but both are correct.

Can I change the word order and say Revisamos uno por uno los errores?

Yes, that’s grammatically correct:

Revisamos uno por uno los errores.

However, the most neutral and common order is:

Revisamos los errores uno por uno. ✅

When you say Revisamos uno por uno los errores, you slightly emphasize the method (“one by one”) earlier in the sentence. It’s OK, but if you’re unsure, stick to:

Revisamos los errores uno por uno.

What’s the difference between revisar, corregir, and repasar?

They are related but not identical:

revisar
- to check, inspect, or go over something to see if it’s correct or in order.
- Focus: looking carefully.
- Revisamos los errores uno por uno.
  We go through the mistakes one by one (to check them).
corregir
- to correct, fix, make right.
- Focus: changing the error.
- Corregimos los errores uno por uno.
  We correct the mistakes one by one.
repasar
- to review, especially in the sense of going over material again to study or reinforce it.
- Repasamos la lección. = We review the lesson.

In Latin America:

revisar is very common for checking documents, tasks, homework, etc.
repasar is very common for studying/reviewing class material.

Your sentence with revisar suggests checking/looking through the errors carefully, not necessarily correcting them.

Could I use the progressive and say Estamos revisando los errores uno por uno?

Yes. That would be:

Estamos revisando los errores uno por uno.
= We are reviewing/checking the mistakes one by one (right now).

Difference:

Revisamos los errores uno por uno.
- Can be a habitual action (we usually do this),
- Or, in the right context, can also describe what’s happening now.
Estamos revisando los errores uno por uno.
- Emphasizes an action in progress right now, similar to English “We’re reviewing…”

Both are correct; choose based on whether you mean general habit or current ongoing action.

Can I replace los errores with a pronoun and say Los revisamos uno por uno?

Yes. Los here is a direct object pronoun referring to los errores:

Revisamos los errores uno por uno.
We review the mistakes one by one.
Los revisamos uno por uno.
We review them one by one.

Use the full noun when you first introduce what you’re talking about:

Primero vemos los ejercicios. Luego los errores. Los revisamos uno por uno.
First we look at the exercises. Then the mistakes. We review them one by one.

So the pronoun los replaces los errores once it’s clear from context.

Is there a difference in Latin American Spanish compared with Spain for this sentence?

For this specific sentence:

Revisamos los errores uno por uno.

There is no real difference between Latin America and Spain. It’s perfectly natural in both.

Small regional notes:

In Spain, you might also hear repasamos los errores if it’s about going over mistakes in a lesson.
In Latin America, revisar is also very common for checking homework, documents, etc.

The verb form revisamos is the same everywhere; what changes regionally is the use of vosotros vs. ustedes, but that doesn’t affect this sentence because the subject pronoun is omitted.

How would I say “Let’s review the mistakes one by one” in Spanish?

You’d use the first person plural imperative (same form as present-subjunctive nosotros):

Revisemos los errores uno por uno.
= Let’s review the mistakes one by one.

This revisemos form is a “let’s…” suggestion directed at “us” (the group including the speaker).